Re: Re: HYB: spots (was another terminology question)
iris@hort.net
  • Subject: Re: Re: HYB: spots (was another terminology question)
  • From: B* C* <b*@ymail.com>
  • Date: Wed, 27 Feb 2013 15:38:11 -0800 (PST)
Thanks Tom for the info and insight.  I think the aphylla derived MTBs have
proven themselves fertile with most classes, with some interesting exceptions,
usually one way or the other (ie pollen sterile and pod fertile, or the
reverse).  I find that interesting from an genetic standpoint and would love
to learn more about it.


Bill





________________________________
 From:
Tom Waters <irises@telp.com>
To: iris@hort.net 
Sent: Wednesday, February 27,
2013 1:41 PM
Subject: Re: [iris] Re: HYB: spots (was another terminology
question)
 
A very typical tet MTB parentage is seen in 'Classic Image'. Of
its four 
grandparent, three are ((aphylla X TB) x TB), the fourth is TB x TB.
If 
aphylla and TB chromosomes were not homologous, those first three
grandparents should have been sterile, yet two produced a fertile seedling
crossed with each other, and the other produced a fertile seedling crossed
with a TB. Furthermore, 'Classic Image' itself is fertile, and when crossed
with an (aphylla x TB) seedling produced 'Saucy', which is also fertile.
This
is not to say that aphylla chromosomes are as homologous with TB 
chromosomes
as the TBs are amongst themselves, just to say the aphylla x TB 
seedlings
behave more like tetraploids than like amphidiploids.
Tom


  

Tom Waters 
Telperion Oasis ~ www.telp.com/irises    


Cuyamungue, New Mexico, USA (zone
6)  

----------------------------------------
From: "Chuck Chapman"
<irischapman@aim.com>
Sent: Wednesday, February 27, 2013 11:38 AM
To:
iris@hort.net
Subject: Re: [iris] Re: HYB: spots (was another terminology
question) 

I'm just going on what I recall. Re-reading the paper would help.
But remember we have even more generations of SDB X SDB crosses, and 
they
still are amphidiploids.

If  mismatching is only a few chromosomes. sorting
out will happen over 
time. If like SDB, number of generations won't make a
difference.

Chuck Chapman

-----Original Message-----
From: Tom Waters 
To:
iris 
Sent: Wed, Feb 27, 2013 12:58 pm
Subject: Re: [iris] Re: HYB: spots (was
another terminology question)

Surely not so mismatched as to function as
amphidiploids, not with all 
the
hundreds of advanced-generation aphylla/TB
hybrids (tet MTBs) that have
been produced with multiple backcrossings, etc.
Tom Waters

Telperion Oasis ~ www.telp.com/irises

Cuyamungue, New Mexico, USA
(zone 6)

----------------------------------------
From: "Chuck Chapman"
Sent: Wednesday, February 27, 2013 5:10 AM
To: iris@hort.net
Subject: Re:
[iris] Re: HYB: spots (was another terminology question)

I vaguely something.
Unfortunately I don't have time this week to look
it up.  but from what I
think I recall, basically it was that aphylla
chromosomes didn't match up well
with the TB chromomes, even if same
number is set. So that  crosses with 
aphylla X TB were amphidiploid.

We are very lucky with iris species, with so
many being able to  cross
and be fertile. This is possible with  many  closely
related species
that are  tetraploids, just because of having two sets   of
chromosomes, you get amphidploid , and thus fertility. But we also have
many 
diploid interspecies crosses that are fertile. This is not the
usual situation
with diploids, in the plant kingdom.  It is precisely
because of this that we
are able to combine so many genes and get such
a wide variety of plants,
colours etc.

When I look  across so many plant  genus, Iris seem to  be rater
exceptional in number of species that can  interbreed and produce
fertile
offspring.  I haven't seen anything  even close, in other
genus. eg Roses ,
daylilies, carnations,  violets, tomatoes, etc,
usually involve no more then
about 20 (daylillies)  the others are much
less. With iris we seem to have  at
least 100.

Chuck Chapman

-----Original Message-----
From: Bill Chaney
To:
iris
Sent: Tue, Feb 26, 2013 6:25 pm
Subject: Re: [iris] Re: HYB: spots (was
another terminology question)

I seem to remember someone once quoting a Bee
Warburton article on this
issue.
  Does anyone happen to know if that is true,
or better yet have a copy
of such
an article?  I think it was in relation to
crosses with I. aphylla
specifically.

________________________________
From:
Tom Waters

To: iris@hort.net
Sent: Tuesday, February 26, 2013 1:41 PM
Subject: Re: [iris] Re: HYB: spots (was another terminology question)

There
have been observations of four pumila chromosomes pairing with four
TB
chromosomes in IBs and (I think) 36-chromosome MDBs. These unbalanced
tetraploids are not completely infertile by any means, and relatively
fertile
ones seem to be becoming more common with time, which I have no
explanation
for. Some used to give a "rule of thumb" that if the bivalents
outnumber the
univalents, some fertility can be expected. If you have the
pairing of four
chromosomes I mentioned, an IB has 12+4=16 bivalents, and
8+4=12 univalents.
We also see partial fertility in the 1/4 aril arilbreds.
I think the
supposition is that unpaired chromosomes do not necessarily
stop the plant
from making gametes, and the unpaired ones just end up in
the gametes
randomly. It's possible to have a viable plant with one of two
extra
chromosomes (or one or two missing ones); these are aneuploids. So
the
fertile
gametes from these unbalanced tetraploids are those that
randomly
receive an
approximately complete set. The probability of that is
small, but
can be great
enough to get some good seeds in some cases.
Tom

Tom
Waters

Telperion Oasis
~ www.telp.com/irises

Cuyamungue, New Mexico,
USA (zone 6)
----------------------------------------
From: "Bill Chaney"

Sent: Tuesday,
February 26, 2013 12:02 PM
To:
"iris@hort.net"
Subject: Re: [iris] Re: HYB:
spots (was
another terminology question)

I don't want to distract the
discussion that
is ongoing, but I can't
resist
jumping in when Chuck brings up
the 12/12/8/8
ploidy because I am trying
to
understand how some of these IBs
are so fertile
with TBs and MTBs.
Especially
if the 12/12 side comes from
aphylla
background.  Would anyone care to
comment
on that or point me to a
good
source of information?

Thanks
Bill
________________________________
From:
Chuck Chapman
To: iris@hort.net
Sent: Tuesday, February 26, 2013 8:06 AM
Subject: Re:
[iris] Re: HYB: spots (was another terminology question)
Amphidiploid is
12/12/8/8  these are SDB

There can't be cross overs between
any chromosome
from 8 set and 12 set, as they never pair up in meiosis.
Crossovers only
occur
in paired chromosomes. No pairs = no crossovers. Like,
never ever. If they
ever did, their would be unbalanced chromosomes, and  it
wouldn't be
viable.
that is  the  meiotic cell would die, or any zygote
formed
would die.

IB is
12/12/12/8 So can be pumilla spot, on one of the
chromosomes
from the  "8
chromosomes"  set.

RE; Chocolate Truffle.  TB X
pumilla = SDB 
No exceptions.
And for kickers, ruffles" a recessive trait that
just isn't
present in
pumilla
species. So where are genes for ruffles coming
from? 
Hell's Fire is a
reddish
black, with  multiple dosages of Ae (check
pedigree) 
Thus  all seedlings
will
be purple in a cross with a yellow. So
are you still
believing this
pedigree?
Chuck Chapman

-----Original
Message-----
From: Linda
Mann

To: iris
Sent: Tue, Feb 26, 2013 10:41 am
Subject: Re: [iris] Re: HYB:
spots (was another terminology question)
Amphidiploid version could.

On
2/26/2013 9:09 AM, Chuck Chapman wrote:
> The
pumilla spot is only on the "8
chromosome" set. So can't show up
in TB,
Agree, spots are interesting.

TB
e-register from pumila, first generation.
There is another one
registered as a
TB, but class is probably a typo - it's
IB height.
Others SDB breeding?
fertile IBs? cross overs?

CHOCOLATE TRUFFLE
  (Mark Grumbine, R. 2006) Sdlg.
MG04-407-7. TB, 29"
(74 cm), EM     S. light
yellow-brown; F. dark mahogany
brown, light
yellow area around beards and
shoulders; beards orange; ruffled.
Hells
Fire X I. pumila, yellow

eagerly
waiting to see the '39 checklist
(Mike, any more TBs registered
from that era
from pumilas?)

Are there more? 
What about the pumila spot work that Blyth
was doing,
trying to bring spot
'up' to TB size? Zing Me.
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS
---------------------------------------------------------------------
To
sign-off this list, send email to majordomo@hort.net with the
message text
UNSUBSCRIBE IRIS

---------------------------------------------------------------------
To sign-off this list, send email to majordomo@hort.net with the
message text UNSUBSCRIBE IRIS
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index